The invention relates to a process for MSG-soldering of metallic materials with use of soldering materials and an electric arc with consumable electrode or non-consumable electrode, whereby the shielding gas contains one or more inert gas components. MSG-soldering is a type of soldering generally known as brazing in which metals having a high melting temperature are used as bonding materials, rather than the type of soldering in which the melting temperature of metals used as a bonding material is low.
The invention further relates to the use of a shielding gas that contains one or more inert gas components for MSG-soldering of metallic materials with use of soldering materials and an electric arc with consumable electrode or non-consumable electrode.
In the industrial application, welding for connecting metallic materials has been established for a long time. During welding, the materials that are to be connected are melted.
During metal-shielding gas-welding (MSG-welding), an arc burns in a shielding gas shell. As a process variant of the MSG-welding, on the one hand, the metal-inert gas-welding (MIG welding) or the metal-active gas-welding (MAG-welding) is mainly used with consumable electrode, and, on the other hand, the tungsten-inert gas-welding (TIG-welding) is used with non-consumable electrode. The tungsten-plasma-welding (TP-welding) further represents an additional process variant of MSG-welding with non-consumable electrode. The units and devices that are necessary for MSG-welding are well known among experts.
Despite the abundance of welding processes with variants that have been developed in the meantime and that are available, however, possible applications for soldering as an alternative to welding are offered.
Thus, for example, the welding of galvanized, aluminized or otherwise coated materials entails problems. The gases that are produced by a low zinc-evaporation point when galvanized sheets are connected thus disrupt the arc during welding and result in instability of the arc. Pores and welding spatter result from this.
MIG- and TIG-soldering are therefore used as efficient and also economical alternatives to conventional welding techniques. A thermal process for continuous joining of materials is referred to as soldering, whereby a liquid phase is produced by melting solder (soldering material). During soldering, in contrast to welding, the solidus temperature of the materials to be connected is not reached.
The MIG- or TIG-soldering is a hard-soldering process, in which the soldered joint is produced with use of MIG- or TIG-shielding gas welding devices. During MIG- or TIG-soldering, the basic material is not melted, but rather a hard-soldering connection of the materials is produced. The soldering materials that are used have comparatively low melting points on the order of up to about 1000xc2x0 C. (e.g., 600 to 700xc2x0 C.)
During MIG- or TIG-soldering, argon, helium or a mixture of argon and helium is usually used as a shielding gas.
Problems also occur once in a while during MSG-soldering under inert shielding gases (MIG- or TIG-soldering), however. For example, there are always arc instabilities, which entail considerable quality loss.